1) doing some kind of output (print_string or Printf.printf) uses
floating point stuff. I didn't have the FPU enabled yet so that threw
and undefined exception. Not sure if the float is used somewhere in
the IO layer or if that triggers something in the GC that uses floats.
Might not even be IO related at all but caused by allocating a heap
value. The simple tests that succeeded before all only used stack.

2) malloc() needs to return 8 byte aligned blocks or storing 64bit
values fails. Doing output initializes the stdout channel, which calls
lseek64 and stores the resultint int64_t.


So now I have ocaml running barebone on my RaspberryPi in a verry
minimal way.

ToDo:
- LED module (turn on/off the OK LED)
- Framebuffer / Graphics modules
- Timer module
- implement free()
- Threads
- USB module
  + keyboard
  + mouse
  + ethernet
- tcp/ip stack

- audio
- GPIO module

If anyone is interested I can upload what I have so far to github. But
beware it is verry much a WIP.